Five-Grain Levain

Ingredients

Ingredient	Overall	Baker's percentage	Liquid-levain	Soaker	Final dough
High gluten flour	300 g	50%			300 g
Bread flour	150 g	25%	150 g
Wholewheat flour	150 g	25%			150 g
Cracked rye	55 g	9%		55 g
Flaxseeds	55 g	9%		55 g
Sunflower seeds	45 g	8%		45 g
Oats	45 g	8%		45 g
Water^†	580 g	97%	185¹ g	240² g	155³ g
Salt	15 g	3%		4 g	11 g
Yeast	5 g	1%			5 g
Mature culture			30 g
Liquid levain					335^* g
Soaker					444 g
Total	1400 g		365 g	444 g	1400 g

*	30g of liquid levain are removed from the build to maintain the culture prior to mixing the dough ingredients.
^†	¹room temperature for the liquid levain starter ²boiling water for the soaker ³warm water for the final dough - temp calculated to form final dough temp of 24-25℃; see Bread formulas and techniques#Desired dough temperature

Liquid Levain. Make 12 to 16 hours before mixing final dough - cover and keep at 21℃
Soaker. At the same time make the soaker by boiling the water and pouring over the rest of the ingredients and mix thoroughly. Cover.
Mixing. The following day, reserve 30g of the liquid levain to maintain the culture and add the remainder to the soaker and other ingredients. Add all the final dough ingredients, including levain and soaker, to the bowl of a mixer. Mix for 3 minutes at low speed (Kenwood 1), check that all the dry ingredients are fully incorporated, and then for 3½ minutes a higher speed (Kenwood 2). The desired dough temperature is 24-25℃
Bulk fermentation. 1 to 1½ hours, Folding once half way through.
Dividing and shaping. Divide the dough into 2 pieces, or leave as one piece for larger loaf. Form the loaves, and place either in baking tins or bannetons.
Final fermentation. Approx 1 hour at 25%, or somewhat longer at room temperature.
Baking. Bake with steam at the beginning, at 240℃ for 10-15 minutes, and then a further 30 minutes at 210℃. Due to the high amount of water in the bread be sure to bake thoroughly.

Jeffrey Hamelman Bread : A Baker's Guide of Techniques and Recipes